Heating furnace and method of operating the same



Nbv. 2 1926, 1,605,630

. C. P. WATKINS HEATING FURNACE AND METHOD OF OPERATING THE SAME Filed June l6 1925 3 Sheets-Sheet 1 who,

MICE 4% 1 Nov. 2 1926.

C. P. WATKINS HEATING FURNACE AND METHOD OF OPERATING THE SAME Filed June 16 1925 3 Sheets-Sheet 2 INVENTOR CW WJQJw- Nov. 2 1926.

c. P. WATKINS HEATING FURNACE AND METHOD OF OPERATING THE SAME 3 Sheets-Sheet 3 Filed June 16 I 1925 INVENTOR Patented Nov. 2, 1926.

UNETED STATES PATENT FFEQE.

crmnLns r. WATKINS, or AMBRInen, PENNSYLVANIA, ASSIGNOR T TATE-Jonas &

GDMPANY, INCORPORATED, OF PITTSBU PENNSYLVANIA.

BGH, PENNSYLVANIA, A CORPGRATIGN 6F HEATING FURNACE AND METHOD OF OPERATING TIT-IE SAME.

Application filed June 16, 1925.

This invention relates to furnaces, and is particularly useful in connection with furnaces of the side-fired type such, for ex ample, as those used for heat treating or annealing exceptionally large material which demands a furnace having an unusually high heating chamber, although the in vention is equally applicable to numerous other types of furnaces.

l0 7 I have found that in certain furnaces, particularly where they are of considerable di mensions, the burners which are ordinarily used for maintaining the furnace at the do sired temperature are not immediately effective for bringing all portionsof the furnace up to the desired temperature at a uniform rate. In fact, this defect is so noticeable in certain cases that the quality of the heat treatment varies markedly in different parts 2 of the furnaces, at times to such an extent that the articles being treated are unfit for.

use. I provide for bringing a furnace to a desired temperature condition by'operating a plurality of heaters and then maintaining such condition by operating only a portion of those heaters. For example, in a car type treating furnace I find it desirable to provide burners adapted to heat the entire furnace by radiation from the roof thereof and also to provide one or more supplemental burners near the fioor of the furnace, which latter are used only when the furnace is be ing brought up to the desired temperature, or for the purpose of equalizing the temperature throughout the height of the material being treated.

In the accompanying drawings, illustrating a preferred embodiment of my invention:

Figure 1 is an end elevation, partly broken away, of a side fired car type furnace embodying my invention;

Figure 2 is a vertical section on the line IIII of Figure 1;

Figure 3 is a horizontal III-III of Figure 1;

Figure 4 is a vertical section on the line IV-IV of Figure 1; and

Figure 5 is a vertical section on the line V-V of Figure 4.

In the illustrated embodiment of my invention, there is shown a furnace having a treating chamber 2 and a floor 3 in the form of a Wheeled truck adapted to be moved in section on the line Serial No. 37.524.

and out of the furnace on tracks 4. The articles to be treated are placed on the truck and moved into the furnace, after which the door 5 is closed to shut off the furnace from outside conditions. A cable hoist, indicated by the reference character 6, is pro vided for operating the door and a counterveight 7 is also provided for reducing the work to be done by the hoist.

The furnace is provided along each side with a plurality of burners 8, all leading into a common space 9 separated from the heating chamber 2 by a baffle Wall 10. This wall is built u immediately in front of the burners, as in icated at 11 in Figure 2. The burners 8 are provided for maintaining the desired furnace temperature and the baliie wall is provided in order that all parts of the furnace may be maintained as nearly as possible at a uniform heat. This uniform temperature condition may be enhanced by suitably regulating dampers 12 placed in the passages connecting the flue openings 13 with the stacks 1 1. A plurality of these flue openings is provided and by suitably regulating the dampers the path of the pro-ducts of combustion from the burners may be regulated as desired so as to attain the de sired temperature conditions throughout the furnace. It will be noted that the flue openings 1 8 are adjacent the floor of the furnace so that the products of combustion first pass upwardly over. the baffle wall 10 and then downwardly to the flue openings. Uniformity of temperature throughout the furnace is also occasioned by the fact that the furnace arch is heated by the gases as they pass over the baffle wall and serves to heat the treating chamber 2 by radiation.

I have found, however, that in many cases this apparatus is not alone riving at the desired temperature conditions. This is especially true in the larger furnaces, and I therefore provide for supplemental heating of certain portions of the furnace in order to bring all parts of the furnace up to the desired temperature condition. To this endv burners 15 are provided adjacent the floor of the furnace. The hot gases from the burners 15 pass through a chamber 16 over a-bafiie Wall 17 and through openings 18 to the heating chamber 2.

It will be seen that the openings 18 are remote from the burner openings 8 but are effective for ar relatively nearer the flue openings 13. The burners 15 are preferably utilized only when the furnace is first put into operation and they are effective for bringing the lower portions of the heating chamberv up to the desired temperature conditions. They may be afterwards turned out if desired, and it is found in practice that the burners 8 are effective for maintaining the desired temperature condition throughout the furnace, although they would not be effective for originally bringing about this desired temperature throughout the furnace, at least not within a period of time which would render such operation desirable.

I thus provide a furnace wherein heat is applied at desired portions of the furnace and portions remote therefrom are specially heated to bring such portions to a desired temperature condition at a uniform rate, after which only the first mentioned ap plication of heat is relied upon in the operation of the furnace. It is possible to quickly bring a furnace up to the desired temperature throughout and to thereafter nmintain such condition substantially constant.

lVhile I have described and illustrated a typical furnace wherein it is desired to maintain conditions uniform throughout the heating chamber, it will be understood that my invention n'iay be utilized, if desired, to bring about varying conditions in the furnace and to thereafter maintain such conditions.

lVhile I have illustrated the invention as applied to a heating furnace for a particular purpose, it will be understood that the invention is in no way limited to such embodiment but may be applied to other types of furnaces or heat treating chambers within the scope of the following claims.

I claim:

l. The method of operating a furnace which includes applying heat at a desired portion of the furnace, specially heating a portion of the furnace remote there-from to bring such portion to a desired temperature condition, and thereafter utilizing only the first mentioned application ofheat, substantially as described.

2-. The method of operating a furnace which includes applyingheat adjacent the roof thereof, specially heating a portion of the furnace remote from the roof to bring such portion to a desired temperature condi tion, and thereafter applying heat only adjacent the roof, substantially as described.

[he method of operating a furnace which includes passing heated gases through the furnace from a source to an outlet, supplying additional heat from a point nearer than said source to said outlet to bring the furnace up to a desired temperature condition, and thereafter utilizing only the first mentioned application of heat to the furnace, sul stan'tially as described.

i. In combination with a furnace, means for supplying heated gases to the furnace chamber, an outlet remote from the supply means but in the same furnace chamber, and supplemental heating means in said furnace chamber nearer the outlet, substantially as described.

5. In combination with a furnace, means for-supplying heated gases to the furnace chamber, an outlet for such gases remote from the supply means but in the same furnace chamber, and a supplemental burner in said chamber nearer the outlet, substantially as described.

6. In combination with a furnace, having a heating chamber, means for supplying heated gases to the furnace, a baffle wall. between such means and the heating chamber, an outlet in the wall of the heating chamber for such gases, and supplemental heating means in said chamber nearer than the firstmentioned supplying means to the outlet, substantially as described.

7. The method of operating a furnace having a plurality of heaters located at differentparts of the furnace, which includes bringing the same to a desired temperature condition by operating heaters in the several parts of the furnace, and then maintaining such condition by operating only a portion of such heaters, substantially as described.

In testimony whereof I have hereunto set my hand.

CHARLES P. WATKINS. 

